Low profile receiver

ABSTRACT

A receiver having a horizontally elongated chamber within a housing, the chamber having a convex triangular cross-section and a dump flap defining a bottom vertex of the triangular cross-section, with a horizontal air/vacuum resin material inlet connecting to the chamber, and a horizontal air/vacuum outlet leading from and connected to the chamber.

CROSS-REFERENCE TO RELATED PATENT APPLICATION

This patent application is a continuation-in-part of U.S. Ser. No.29/550,569 entitled “Low Profile Receiver” filed 5 Jan. 2016 in the nameof Stephen B. Maguire; the priority claim is made under 35 USC 120.

BACKGROUND OF THE INVENTION AND DESCRIPTION OF THE PRIOR ART

The terms “air/vacuum”, and “vacuum/air” and “air/vacuum stream”, etc.are used synonymously and interchangeably herein to denote a movingstream of air, at sub-atmospheric pressure, drawn by a vacuum pump. Suchmoving “air/vacuum” streams are conventionally used to convey granularplastic resin material in facilities in which the granular plastic resinis molded or extruded into finished or semi-finished plastic parts.

“Receiver” is a term used in the plastics industry to denote devicesthat temporarily hold granular plastic resin material before thatgranular plastic resin material is loaded into a hopper for subsequentprocessing by a compression or injection molding press or an extruder.As used herein, the term “process machine” denotes collectively suchcompression molding machines, injection molding machines and extruders.

Receivers typically include a vacuum chamber that effectively pullsgranular plastic resin material into the receiver due to the vacuum thatexists within the vacuum chamber. A vacuum pump is connected to thereceiver to create the vacuum required within the vacuum chamber to pullgranular plastic material into the receiver. This facilitates moving thegranular plastic resin material from a remote location to a hopper, tobe fed by the receiver, with the hopper being typically located over aprocess machine. The receiver and the vacuum pump are typically part ofa larger resin conveying system that conveys the granular plastic resinfrom a supply to the receiver.

Receivers may be located over surge bins or over other temporary storageunits in addition to hoppers.

Receivers load in cycles. Specifically, the receiver loads with granularplastic resin material and then dumps the granular plastic resinmaterial as one operating cycle. Accordingly, the receiver requires somesort of a collection bin or surge hopper below the receiver to receivethe granular plastic resin material as it is fed to the process machine.

Typically the vacuum source is remote, namely it is not integrated intothe receiver itself. The receiver, in its most simple, elementary form,is a simple chamber that has a vacuum line connected to it to pull airfrom the chamber to create a vacuum inside the chamber. The vacuum thendraws granular plastic resin material into the chamber portion of thereceiver. The receiver accordingly has a material line connected to itfor granular plastic resin material to flow in or, more accurately, tobe pulled in by the vacuum, into the chamber portion of the receiver.The receiver typically has a valve or gate at the bottom of the receiverto allow the granular plastic resin material to drop out of the bottomof the receiver when the vacuum is broken or removed or when the valveor gate is otherwise opened electrically or pneumatically. Since thereceiver has a storage area with a relatively large volume andcross-sectional area relative to the conduit through which theair/vacuum and granular material mixture travels, when the mixturereaches the receiver storage area, speed of the moving air/volume streamdrops. The kinetic energy of the stream is no longer sufficient to carrythe granular resin, so the resin falls to the bottom of the receiver.

All known receivers have these characteristics in common.

SUMMARY OF THE INVENTION

An important characteristic of the inventive low profile receiver is thevery low profile the receiver offers when installed. Process machinesoften have a number of auxiliary items mounted above the throats of theprocess machines. These may include magnetic drawers; additive feeders;simple material hoppers; large drying hoppers; gravimetric blenders; andother devices. A receiver is typically mounted on top of this collectionof equipment. Such a stack-up of items may interfere with overheadrestrictions or limitations such as the ceiling or a mezzanine in aplastics processing facility. Access to the receiver for service mayalso be a problem. Safety issues arise with excessive height.

In the low profile receiver according to the invention, in oneconfiguration the receiver adds only 7 inches of height. This is to becontrasted to current receiver designs that require from 15 to 25 inchesof added height due to their configuration.

The low profile receiver of the invention includes a filter blow off,which clears the entire filter effectively. The cleaning is so effectivethat it virtually eliminates periodic filter cleaning that is requiredby conventional filter blow off designs in known receivers.

True full range cloth filters, when used in conventional receiversalways clog, and accordingly, conventional receivers most often use onlymetal screens for filters. The metal screen stops the granular resinmaterial pellets, but does not stop or catch dust and fines. The passageof dust and fines requires an additional filter at the vacuum pump tocatch the dust and the fines which otherwise would damage the vacuumpump.

The low profile receiver of the invention includes a full cloth filterthat stops dust and fines; the full cloth filter is easily cleaned everycycle by the filter blow off device.

In one of its aspects, this invention provides a receiver having ahorizontally elongated body with an interior chamber. A horizontalgranular plastic material inlet conduit communicates with the interiorchamber of the elongated body. A horizontal vacuum outlet conduitconnects to the elongated body. A removable dust and material fines,preferably cloth, filter is positioned between the inlet and outletconduits and collects dust and material fines before the dust andmaterial fines can enter the vacuum outlet conduit leading to the vacuumpump. With the cloth filter catching the dust and material fines, nofilter is required at the vacuum pump.

The receiver further includes a blaster for directing an air blast atthe filter in order to clean the filter of retained dust and materialfines. An outlet dump flap extends the longitudinal length of a lowerextremity of the longitudinally elongated housing portion of thereceiver in which the granular resin material is stored. The outlet dumpflap is movable between an open position at which granular plasticmaterial in the housing can flow freely downwardly out of the housing,and a closed position at which the dump flap defines a part of thebottom of the chamber. With the dump flap extending the horizontallongitudinal length of the housing, the housing empties essentiallyinstantaneously when the dump flap moves to the open position. As aresult, the receiver empties much faster than know receivers.

The receiver body is preferably wider than it is high and preferably hasa generally convex triangular transverse cross-section.

In yet another one of its aspects, this invention provides a method fortemporary storage of granular resin material prior to processing thereofinto a finished or semi-finished product by molding or extrusion. Themethod includes feeding an air/vacuum stream carrying the granular resinmaterial in a first horizontal direction into a chamber under vacuum.The method proceeds by reducing velocity of the air/vacuum stream in thechamber, thereby causing granular material entrained the stream to fallto the chamber bottom. The method proceeds with passing the stream in asecond horizontal direction through a filter and releasing the streamfrom the chamber in the first horizontal direction. A flap defining abottom of the chamber swings to an open position in response to theweight of the material, permitting granular material to fall from thechamber.

In still another one of its aspects, this invention provides a receiverthat has a longitudinally elongated body having an interior chamberextending the length of the body. A horizontal conduit is provided forinlet of an air/vacuum stream carrying granular resin material andcommunicating with the interior chamber of the elongated body. Ahorizontal air/vacuum outlet conduit is connected to the interiorchamber of the elongated body. A dump flap extends horizontally along alower extremity of the interior chamber and is movable between an openposition at which granular plastic material in the chamber can flowfreely downwardly out of the chamber, and a closed position at which theflap defines a bottom portion of the chamber.

In this aspect of the invention, the receiver has a dump flap extendingthe horizontal length of the chamber interior and further includes adust and material fines filter between the inlet and outlet conduits forcollecting dust and material fines before entering the vacuum outletconduit, and further includes a blaster for directing an air blast atthe filter to clean the filter of retained dust and material fines. Thedump flap is movable rotationally between open and closed positions; thebody of the receiver is wider than it is high; the dump flap swingsunder the influence of gravity to a closed position when the chamber isempty; the filter is a cloth filter; the inlet for the granular plasticmaterial is in a lateral, vertically extending surface of the receiver.

In still further portions of this aspect of the invention, the outletfor the air/vacuum stream is in the lateral surface of the receiver; thebody of the receiver has a convex triangular cross-section; the chamberhas at least one convex wall; the chamber is longer than it is high, andthe chamber is longer than it is wide.

In yet another one of its aspects, this invention provides a method fortemporary storage of granular resin material prior to processing thereofinto a finished or semi-finished product by molding or extrusion, wherethe method includes feeding an air/vacuum stream carrying the granularresin material horizontally into a chamber under vacuum. The methodproceeds with reduction of velocity of the stream in the chamber,thereby causing granular material entrained in the stream to fall to thechamber bottom. The method next continues to draw the stream from thechamber thereby maintaining vacuum in the chamber. The method mayconclude by releasing the vacuum horizontally from the chamber. A flapdefining a bottom of the chamber swings to an open position due to theweight of the granular material resting in the bottom of the chamber,permitting granular material resting on the flap to fall from thechamber. In this aspect of the invention, desirably the air/vacuumstream passes through a cloth filter. Most desirably, the passing of thestream through the cloth filter is performed before releasing the vacuumfrom the chamber. Further desirably the stream passes horizontallythrough a cloth filter perpendicular to the stream.

In still another one of its aspects, this invention provides a receiverhaving a horizontally elongated chamber, where the chamber has a convextriangular cross-section. The chamber includes a dump flap defining abottom vertex of the triangular cross-section. A horizontal air/vacuumresin material mixture inlet connects to the chamber while a horizontalair/vacuum outlet leads from the chamber and is connected to thechamber. A modular control section is removable from the housing withinwhich the chamber resides, and manually actuable clips releasably retainthe control segment in engagement with the housing.

In still another one of its aspects, this invention provides a receiverhaving an longitudinally elongated body, with an interior chamberextending the length of the body. A horizontal conduit for inlet of anair/vacuum stream carrying granular resin material communicates with theinterior chamber of the elongated body. A horizontal air/vacuum outletconduit connects to the interior chamber of the elongated body. A dustand material fines filter between the inlet and outlet conduits isprovided for collecting dust and material fines and is positioned forfiltration of the stream before entering the vacuum outlet conduit. Thereceiver yet further comprises a blaster for directing an air blast atthe filter, in a direction opposite to that of the vacuum/air streamwhen it flows through the filter, to clean the filter of retained dustand material fines, and a dump flap extending horizontally along a lowerextremity of the interior chamber, where the dump flap is movablebetween an open position at which granular plastic material in thechamber can flow freely downwardly out of the chamber, and a closedposition at which the dump flap defines a bottom portion of the chamber.

In the preferred embodiment of the receiver, the dump flap is pivotablebetween a closed position and a housing open position. The outlet dumpflap is weighted to swing to a closed position under the force ofgravity and to remain closed in response to vacuum drawn within thereceiver, allowing the receiver to fill. Once the vacuum draw to thehousing portion of the receiver, in which the granular resin materialconveyed into the receiver by an air/vacuum stream collects, is shutoff, there is no internal vacuum force retaining the receiver dump flapin the closed position. The weight of the granular resin material on thedump flap causes the dump flap to move to the open position and thegranular resin material falls downwardly, out of the receiver, due togravity.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of a low profile receiver in accordance withthe invention, in which the top, left side and left end of the receiverare visible.

FIG. 2 is a view in elevation of the left or front end of the receiverillustrated in FIG. 1, with the receiver dump flap in the open position.Section lines 8-8 and 9-9 in FIG. 2 indicate where sections are takenthat are presented in FIGS. 8 and 9 herein.

FIG. 3 is a view in elevation of the right or rear end of the receiverillustrated in FIGS. 1 and 2, with the receiver dump flap in the openposition.

FIG. 4 is a view of the right side receiver illustrated in FIGS. 1, 2and 3, with the receiver dump flap in an open position.

FIG. 5 is a view in elevation of the left side of the receiverillustrated in FIGS. 1, 2, 3 and 4, with the receiver dump flap in anopen position.

FIG. 6 is a view of the top of the receiver illustrated in FIGS. 1, 2,3, 4, and 5.

FIG. 7 is a view of the bottom of the receiver illustrated in FIGS. 1through 6, with the dump flap in an open position for discharge ofgranular resin material.

FIG. 8 is a sectional view of the receiver illustrated in FIGS. 1through 7 taken at lines and arrows 8-8 in FIG. 2, where the dump flaphas been illustrated in the open position.

FIG. 9 is a sectional view of the receiver illustrated in FIGS. 1through 8 taken at lines and arrows 9-9 in FIG. 1, with the dump flapillustrated in the closed position.

FIG. 10 is an exploded schematic view of the receiver illustrated inFIGS. 1 through 9 showing the modular construction of the receiver.

FIG. 11 is an exploded isometric view of the receiver illustrated inFIGS. 1 through 10 showing the receiver parts in detail.

FIG. 12 is an exploded isometric schematic view of certain components ofthe receiver illustrated in FIGS. 1 through 11, with lines andarrowheads provided to illustrate the flow of the conveying vacuum/airstream and conveyed granular resin material through the receiver.

FIG. 13 is a broken end view of the lower portion of the left end of thereceiver illustrated in FIGS. 1 through 12 depicting the discharge chuteand the left triangular portion of the dump flap, with the dump flap inan open position.

FIG. 14 is a broken end view of the lower portion of the receiverillustrated in FIGS. 1 through 13 depicting the discharge chute and theleft triangular portion of the dump flap, with the dump flap in a closedposition.

DETAILED DESCRIPTION OF THE INVENTION

Referring to the drawings and particularly to FIG. 1, a receiver inaccordance with the invention is designated generally 10. A horizontalmaterial inlet tube 12 receives a moving air/vacuum stream carryinggranular resin material for temporary storage of the granular resinmaterial in receiver 10. Horizontal material inlet tube 12 is mounted ina vertically oriented first end plate 30. Also mounted in first endplate 30 is an air actuated piston-cylinder combination 14, whichcontrols air/vacuum flow through receiver 10 in an on-off manner asdescribed below.

A control section 17 of receiver 10 is maintained within a controlsection wrapper 18, where the control section wrapper 18 is illustratedin FIG. 1. Receiver 10 further includes a housing 20, which serves as agranular material storage receptacle or chamber for temporary storage ofgranular resin material therein. Control section wrapper 18 and thecomponents therein are secured to housing 20 via several clip-typelatches 24, two of which are visible in FIG. 1. These clip-type latchesfacilitate quick disassembly of receiver 10, allowing control section 17within control section wrapper 18 to quickly be removed from theremainder of receiver 10 for adjustments, repairs, replacing the filter,and the like.

Receiver 10 further includes a horizontal outlet line 28 via which anair/vacuum stream is drawn from receiver 10 by a vacuum pump, which isnot illustrated in the drawings. In FIG. 1, a portion of an inlet endhorizontal blow-back support plate 74 is visible, extending out fromunder control section 17, which is not visible or numbered in FIG. 1 butis shown and numbered in others of the drawings.

As illustrated in FIG. 1 and as particularly well-illustrated in FIGS. 2and 3, housing 10 has convexly curved sides 36, with the sides beingdesignated 36L and 36R for the left and right sides respectively. (Asused herein, the term “left” denotes the portion of the receiver lateralsurface that is visible in FIG. 1 and is to the viewer's right in FIGS.2 and 3.) Still referring to FIG. 2 principally and also in part to FIG.3, at the bottom of sides 36, extending from and fixed to sides 36L and36R are a first bottom flange 32 and a second bottom flange 34, wherefirst bottom flange 32 is longer in the vertical direction than issecond bottom flange 34. Second bottom flange 34 is largely occluded inFIG. 2 by an end portion 16A of a dump flap 16.

Still referring principally to FIG. 2, dump flap 16 is mounted forpivotal movement with respect to a granular resin material dischargechute 38 formed by vertically downwardly extending portions of first andsecond bottom flanges 32, 34, with granular resin material dischargechute 38 running the longitudinal length of housing 20 portion ofreceiver 10 (The vertically downwardly extending portions of first andsecond bottom flanges 32, 34 are not separately numbered in thedrawings). First and second bottom flanges 32, 34 have tabs designated32 a and 34 a, which extend perpendicularly to housing sides 36 andfacilitate fabrication, maintenance and operation of receiver 10.

Respective left and right sides 36 of housing 20 are denoted 36L and 36Rfor the left and right sides of receiver 10, where the left side ofreceiver 10 is the side visible in FIG. 1. When chute 38 is open due todump flap 16 being in the position illustrated in FIGS. 2 and 3 and 13,granular resin material stored within housing 20 flows downwardly out ofreceiver 10 through chute 38 due to gravity.

In FIG. 2, the construction and configuration of receiver 10 isparticularly well-shown. Receiver 10 and particularly housing portion 20thereof are wider at the vertices or angles at which housing top 42meets with sides 36L, 36R; these vertices or angles have been denoted 78in FIG. 2. The ratio of the receiver 10 width, measured as the distancebetween vertices 78, and the height of receiver 10, as measured from thehigh point of housing top 42 to the horizontal support plate 80, both ofwhich are visible in FIG. 2, is about 5:3, meaning that the housing 20of receiver 10 is about 40% wider than it is high.

In FIG. 2, a dump flap is illustrated in the open position, wherebygranular resin material may flow out of receiver 10 through chute 38. Aleft triangular portion of dump flap 16 is denoted 16A in FIG. 2. Alongitudinally extending portion of dump flap 16 is denoted 16C in FIG.2 and is visible only as a pair of closely spaced lines. Longitudinallyextending portion 16C of dump flap 16 runs the longitudinal length ofhousing 20. Dump flap 16 is pivotally movable about a pair of pins 68,one of which is illustrated in FIG. 2.

Continuing to refer to FIG. 2, horizontal material inlet tube 12 and airpowered piston-cylinder 14 are clearly illustrated as being mounted infront plate 50. Note in FIG. 2 that control section wrapper 18 definesan outer periphery of control section 17 and is slightly inboard ofhousing top 42 and housing sides 36L, 36R. Control section wrapper 18connects with a horizontal support plate 80 illustrated in FIG. 2. Stillreferring to FIG. 2, a mounting flange 82 is rigidly secured andconnected to an inlet end horizontal blow-back support plate 74 with aportion extending vertically downwardly therefrom. The downwardlyextending portion of front mounting flange 82 is equipped with a pair ofholes for mounting receiver 10 to associated adjacent equipment asrequired.

Referring to FIG. 3, the generally convex triangular shape, intransverse section, of housing portion 20 of receiver 10 is well-shown,with housing top 42 and housing sides 36L, 36R again appearing in theirtriangular convex shape. The outlet of material outlet line 28 isapparent in a rear end plate 90. A rear mounting flange 84 is mounted onan outlet end horizontal support plate 76 and has upwardly extendingportions equipped with holes for mounting receiver 10 on auxiliaryequipment. First bottom flange 32 is illustrated in FIG. 3. In FIG. 3,dump flap 16 is again visible, with right triangular portion 16B clearlyshown, and with longitudinal portion 16C again appearing as a pair oflines indicating that longitudinal portion 16C runs away from the viewerand is perpendicular to the viewer in FIG. 3. An outlet end horizontalplate 76 is shown in FIG. 3.

Referring to FIG. 4, receiver 10, housing 20, control section wrapper18, material inlet tube 12, air piston-cylinder 14, and material outletline 28 are all well shown. In FIG. 4, the two pins 68 about which dumpflap 16 rotates are clearly shown, as is the longitudinally extendingportion 16C of dump flap 16. A major longitudinally extending flange 16Dand a minor longitudinally extending flange 16E are also visible in FIG.4. FIG. 4, as noted above, depicts dump flap 16 in an open position asillustrated in FIG. 2, FIG. 3 and FIG. 13.

Referring to FIG. 5, first bottom flange 32 is well illustrated asextending longitudinally the length of housing 20 to define a portion ofoutlet chute 38. Lip portion 32A denotes a lip portion of first bottomflange 32; lip portion 32A is also illustrated in FIG. 2. In FIG. 5,dump flap 16 is somewhat occluded by first bottom flange 32 as can beappreciated by comparing FIG. 5 with FIG. 2, and noting that FIG. 5 is aside view, whereas FIG. 2 is an end view. Pins 68, on which dump flap 16is mounted and about which dump flap 16 rotates, are again illustratedin FIG. 5 as are material inlet tube 12, piston-cylinder 14, and outletline 28, as well as inlet end horizontal blow-back support plate 74 andoutlet end horizontal support plate 76.

In FIG. 6, the top of receiver 10, material inlet tube 12, outlet line28, top 42, latches 24, control section wrapper 18 and outlet endhorizontal support plate 76 are all illustrated. Dump flap 16 and thevarious parts thereof and associated therewith are occluded from view inthe top view provided by FIG. 6.

Referring to FIG. 7, showing the bottom of receiver 10 with dump flap 16in the open position, discharge flange 54 is plainly visible as is theopen interior 102 of housing 20. Pins 68, about which dump flap 16rotates, are shown at either end of dump flap 16 engaging left and righttriangular portions 16A, 16B of dump flap 16. Shown in a mannersimilarly to the other views discussed above are material inlet tube 12,piston-cylinder 14, inlet end horizontal blow-back support plate 74,outlet end support plate 76, outlet line 28, and side 36L, 36R ofreceiver 10.

Referring principally to FIGS. 8 and 9, in FIG. 8, dump flap 16 isillustrated in the open position at which granular resin material storedwithin housing 20 self-discharges by means of gravity-induced flow outof housing portion 20 of receiver 10.

Still referring to FIG. 8, the control section for receiver 10 isdesignated generally 17 and includes two interior compartments, numbered110 and 112 in FIG. 8. The first interior compartment 110 is bounded byfront end plate 30 and by a first intermediate plate designated 46 inFIG. 8. Further bounding first compartment 110 is horizontal supportplate 80, effectively forming the floor of both the first and secondcompartments 110, 112, and a suitable cover piece which has not beenillustrated in the drawings for the sake of drawing clarity. Controlsection 17 further includes a second compartment 112 bounded by firstand second intermediate plates 46, 48, by horizontal support plate 80,and by the same upper plate that has not been shown in the drawings toenhance drawing clarity.

First compartment 110 is effectively at ambient pressure, while secondcompartment 112 must be maintained air tight. As such, compartment 112is preferably fabricated by welding first and second intermediate plates46, 48, horizontal support plate 80 and the unnumbered and unshown topplate, as well as sides which are not shown in the drawing, in order toassure air tightness of second compartment 112. Such air-tightconstruction is required in order for blow-back device 60, describedbelow, to function properly.

Further visible in FIG. 8 is a disk 108 which is secured to the pistonrod extending from piston-cylinder 14. Disk 108, when piston-cylinder 14is actuated, serves to close, in an air tight manner, the end of outletline 28, namely the inlet opening thereto.

Surrounding outlet line 28 is a spacer 104 held in place by a cotter pin106 with respect to outlet line 28. Spacer 104 is preferably resilientand serves to maintain the required air tight joint where outlet line 28passes through rear plate 52 and through front housing plate 50. Fronthousing plate 50 shown in FIG. 8 is not to be confused with front endplate 30, which is also visible in FIG. 8 as well as in FIG. 2. Outletline 28 mates with a suitable fitting, not numbered, which receives disk108 to effectuate an air tight seal when piston-cylinder 14 is actuatedand disk 108 assumes the position illustrated in FIG. 8.

Referring to FIG. 9, a preferably cloth filter 22 is mounted in asuitable aperture formed in front plate 50. Adjacent to filter 22 andmounted on first intermediate plate 46 is an air blast device 60 of thetype disclosed in U.S. Pat. No. 8,753,432. Air blast device 60, which issometimes referred to as a “blow-back device”, has its air blast outletaxially aligned with filter 22 and oriented such that when the blow-backdevice 60 delivers a blast of air, the blast of air is directed atfilter 22 and contacts filter 22 at a substantially perpendicular anglethereto. This blast of air provided by blow-back device 60 is desirablyprovided prior to each fill of receiver 10 with granular resin material.Blow-back device 60 keeps filter 22 clean, with dust and fines blown outof filter 22 falling to the bottom of open interior 102 of housing 20.Use of blow-back device 60 and filter 22 assures that no dust or finesare carried with the air/vacuum stream that passes through filter 22into second compartment 112 and on to the vacuum pump.

The required air/vacuum stream is drawn through filter 22 by the actionof a vacuum pump drawing the air/vacuum stream through outlet line 28.Viewing FIG. 8 in connection with FIG. 9, when disk 108 is moved awayfrom the aperture defining the inlet to outlet line 28, namely when disk108 is moved away from second intermediate plate 48, free flow of theair/vacuum stream from the open interior 102 of housing 20 throughfilter 22 and into outlet tube 28 results, due to the air tightconstruction of second compartment 112. By the same token, whenpiston-cylinder 14 is actuated and disk 108 closes the aperture tooutlet tube 28, vacuum is effectively relieved in open interior 102 ofhousing 20.

The weight of any granular resin material residing in open interior 102of housing 20 causes dump flap 16 to rotate to the position illustratedin FIG. 2, where discharge chute 38 is open. At this position, granularresin material stored within housing 20 flows downwardly out of housing20. Note that left and right triangular portions 16A, 16B of dump flap16 are constructed with a geometry that in the absence of any granularresin material in housing 20 they and the remainder of dump flap 16 willrotate to the closed position illustrated in FIG. 14. When vacuum isapplied by draw of an air/vacuum stream at below atmospheric pressurethrough outlet line 28, vacuum propagates back into interior 102 ofhousing 20 through second compartment 112 and filter 22, thereby helpingto retain dump flap 16 in a closed position. Since the pressure in openinterior 102 is lower than atmospheric, this results in an inwardclosure force against dump flap 16.

Referring to FIG. 10, the modular construction of receiver 10 isillustrated. Control section 17 is easily removable from housing 20 inorder to change filter 22 as needed. Screw connections and sealinggaskets as illustrated in FIG. 8 are used to retain control section 17in operating engagement with housing 20. These connections facilitaterapid disassembly of receiver 10 when service is required or a filter 22must be changed. Clips 24 are easily unfastened to release controlsection 17 from housing 20. In FIG. 8 second intermediate plate 48 isspaced from front plate 50. With suitable flexible gaskets 114, 116providing the seal at the aperture defining the inlet to outlet line 28,snaps 24 can be disengaged thereby allowing essentially sliding removalof control section 17 from housing 20.

FIG. 11 shows the receiver and all of its parts with the modularconstruction and separation of control section 17 from housing 20 beingimmediately apparent.

As noted, dump flap 16 has two triangular portions, denoted 16A and 16Brespectively, which are at either end of the dump flap 16. Triangularportion 16A is illustrated in FIG. 2, while triangular portion 16B isillustrated in FIG. 3. Running between triangular portions 16A, 16B is alongitudinally elongated portion 16C of dump flap 16. Elongated portion16C is more visible in FIG. 9 (as well as in FIG. 7), where dump flap 16is illustrated in FIG. 9 in the position closing chute 38 and precludingany downward flow of granular resin material out of housing portion 20of receiver 10. The horizontally elongated portion 16C of dump flap 16is denoted by two closely spaced double lines in FIGS. 2 and 3.

Preferably there is a three wire cable connected to the receivercontrol, leading to the receiver from a power unit which desirablyprovides power to the vacuum pump creating the vacuum to draw theair-material mixture into the receiver. Two of the wires from the powersupply are preferably in the vacuum pump control, which supplies therequired 24 volts to receiver. The third wire is a signal wire. When thereceiver requires granular resin material and the dump flap is closed,this third wire provides power to the signal line and the microprocessorknows to turn receiver 10 on.

Each receiver 10 preferably includes such a microprocessor.Additionally, there is a microprocessor preferably provided in powerunit. The microprocessor in the receiver preferably detects that thedump flap has closed and tells the power unit associated with the vacuumpump to run for a set time period, which has been previously computedand entered into the microprocessor. Otherwise receiver 10 may run untila high material level sensor in receiver 10 is covered, indicatingreceiver 10 is full of granular resin material. A timer portion of themicroprocessor acts as a safety time-out so that receiver 10 does notrun forever in the event of a blockage of granular resin material or inthe event that no granular resin material is available from the source.

Housing top 42 and housing sides 36L, 36R are all curved outwardly. Thisoutward curvature of housing top 42 and housing sides 36L, 36R resiststhe atmospheric pressure producing force against those sides 36L, 36Rand housing top 42. The force of the atmospheric pressure tends to pushthe housing top 42 and housing sides 36L and 36R inwardly due to thevacuum (actually slightly sub-atmospheric pressure) present within thehousing portion of receiver 10 during operation. The curved, convexshape of sides 36L, 36R and housing top 42 facilitate the small size,compact design and high capacity characteristics of receiver 10.

Dump flap 16 and particularly triangular portions 16A, 16B of dump flap16 are configured for pivotal movement of dump flap 16 about pins 68. Asnoted above, the configuration and weighting of dump flap 16, andparticularly the weighting of left and right triangular portions 16A,16B and longitudinal portion 16C of dump flap 16, cause dump flap 16 torotate into the closed position shown in FIG. 13. When dump flap 16reaches the closed position, the vacuum drawn by the vacuum pumpmaintains dump flap 16 at that closed position.

Air cylinder 14 effectively controls flow of air and the air or vacuumand resin material mixture through receiver 10. As illustrated in FIG.8, air cylinder 14 includes a shaft portion extending therefrom with acircular disk 108 being mounted on the extremity of shaft portion 70;the circular disk is designated 108 in FIG. 8. When air cylinder 14 isactuated, shaft portion 70 extends therefrom and circular disk 108closes the opening to outline line 28.

During operation, as receiver 10 is receiving granular resin materialentrained in the vacuum/air stream coming in through material inlet tube12, dump flap 16 is retained in closed position due to the suction forceof the vacuum pump drawing through outlet line 28. Once vacuum is shutoff, either through shut off of the vacuum pump, or through actuation ofair cylinder 14 closing outlet line 28 and thereby precluding furtherdraw of vacuum through receiver 10, or if the weight of the granularresin material becomes great enough to overcome the vacuum suctiontending to keep dump flap 16 in the closed position, dump flap 16 movesto an open position as dump flap 16 is forced open by the weight ofresin material within receiver 10.

During operation dump flap 16 opens due to the weight of the granularresin material pellets residing within housing 20 of receiver 10 andresting on dump flap 16. Without the weight of the granular resinmaterial, or once the granular resin material has flowed out of thereceiver, the dump flap swings closed due to the force of gravity andthe configuration of the dump flap, particularly the geometry of dumpflap left and right triangular portions 16A, 16B, and longitudinallyextending portion 16C. In the normal hanging position, dump flap 16 isclosed, with the exception of a slight gap between the flap surface andthe edge of the opening to the open interior 102 of housing 20.

Dump flap 16 may be held open by a pile of granular resin material whenthe receiver dumps a load of granular resin material onto a pile ofgranular resin material that has just fallen out of receiver 10 and, forexample, is resident in a hopper, not shown in the drawings and not apart of receiver 10, located below dump flap 16. In such case, whengranular resin material is dumped, dump flap 16 opens and the granularresin material may not have room to flow completely out of receiver 10,due to presence of the previously dumped pile(s) being immediately belowreceiver 10.

As granular resin material is used by an associated process machine, anygranular resin material remaining in receiver 10 flows out. When thepile of previously dumped granular resin material below receiver 10drops to a level below dump flap 16, dump flap 16 swings shut andanother batch of granular resin material may be loaded into receiver 10.Vacuum pulls dump flap 16 tight to create a vacuum seal allowing thevacuum feed of an air/vacuum stream carrying granular resin materialinto the open interior 102 of housing 20.

In FIG. 12, receiver 10 is illustrated schematically. Not all of thecomponents of receiver 10 have been numbered or shown in detail in FIG.12 in order to enhance the clarity of the drawing. FIG. 12 depicts theflow of vacuum/air and material through receiver 10.

Specifically, a vacuum/air stream carrying granular resin materialenters receiver 10 via inlet tube 12 as indicated by dotted line andarrows A. The vacuum/air granular material mixture passes into theinterior of housing 20, where the granular resin falls out of thevacuum/air stream in a downward direction due to the force of gravitybecause the air/vacuum stream, having entered a larger air space volume,namely the open interior of housing 20, is at a greatly reduced velocityfrom the air/vacuum stream velocity in a conduit leading to inlet tube12.

At the lower velocity, the granules of resin material fall out of theair/vacuum stream. This flow of the granular resin material downwardlyis indicated by longer dotted lines and arrow B in FIG. 12. Thevacuum/air stream, being pulled by a vacuum pump not shown in FIG. 12,is drawn out of the interior of housing 20 as indicated by arrows C andthe line consisting of long dashes and short dashes in FIG. 12. Thevacuum/air mixture flows out of the interior of housing 20 in adirection towards the control section 17 of receiver 10, in a directionopposite that of arrow A. The vacuum/air stream passes through filter22, where fines and dust are removed from the vacuum/air mixture movingthrough filter 22, with filter 22 being mounted in a filter opening 86.The vacuum/air mixture, having been cleaned of dust and fines turns andenters outlet line 28 through fitting 88, travels through outlet line28, leaving receiver 10 and goes on to a vacuum pump. The granular resinmaterial, upon accumulating to an amount sufficient in weight to causedump flap 16 to open, falls out of the open interior 102 of housing 20in response to gravity.

A major advantage of material inlet tube 12 and outlet line 28 beinghorizontal, and entering and leaving receiver 10 respectively throughapertures formed in vertically extending surfaces of receiver 10,results in receiver 10 having a very low height, thereby providing roomfor other components in a plastic resin processing facility.

I claim the following:
 1. A receiver for temporary storage of pneumaticvacuum delivered granular material prior to processing thereofcomprising: a. an elongated body having a chamber defining a portion ofthe body; b. a conduit for inlet of a pneumatic vacuum stream carryinggranular material, communicating with the interior of the chamber of theelongated body; c. a pneumatic vacuum stream outlet conduit connected tothe interior of the chamber of the elongated body; d. a dust andmaterial fines filter, connected to the chamber for passage of thevacuum stream therethrough, for collecting dust and material fines fromthe vacuum stream before the stream enters the pneumatic vacuum streamoutlet conduit; e. a blaster connected to the chamber for directing ablast of compressed air at the filter in a direction opposite that ofpassage of the stream therethrough to clean the filter of retained dustand material fines; f. a dump flap extending horizontally along a lowerextremity of the chamber, movable between an open position at whichgranular material in the chamber can flow freely downwardly out of thechamber upon cessation of pneumatic vacuum material delivery, and aclosed position, to which the flap is drawn by gravity and maintained byvacuum resulting from pneumatic vacuum material delivery to the chamber,to define the bottom of the chamber.
 2. A receiver for temporary storageof pneumatic vacuum delivered granular material prior to processingthereof comprising: a. a longitudinally elongated body having a convextriangular transverse cross section and a chamber defining a portion ofthe body, the body being wider than it is high; b. a conduit for inletof a pneumatically powered vacuum stream carrying granular material,communicating with the interior of the chamber of the elongated body; c.a vacuum stream outlet conduit connected to the interior of the chamberof the elongated body; d. a dust and material fines filter, connected tothe chamber and positioned for passage of the vacuum streamtherethrough, for collecting dust and material fines from the vacuumstream before the stream enters the vacuum stream outlet conduit; e. ablaster connected to the body for periodically directing a blast ofcompressed air at the filter in a direction towards the chamber interiorand opposite that of passage of the stream through the filter to cleanthe filter of retained dust and mineral fines; f. a bottom flapextending horizontally along a lower extremity of the chamber, movableangularly between an open position at which granular material in thechamber can flow freely downwardly out of the chamber upon cessation ofpneumatic vacuum material delivery, and a closed position to which theflap is drawn by gravity and maintained by vacuum during pneumaticvacuum material delivery to the chamber.
 3. The receiver of claim 2further comprising pins, connected to the body, angularly movablysupporting the bottom flap.
 4. The receiver of claim 2 wherein twovertices of the convex triangular cross section define lateraltransverse extremities of the body.
 5. The receiver of claim 2 wherein avertex of the triangular cross section is at the bottom of the body. 6.The receiver of claim 4 wherein the body extends above the two verticesdefining transverse extremities of the body triangular cross section.